Answer
Correct answer is "S"; the sympathetic branch of the ANS
Work Step by Step
The sympathetic branch (S) of the ANS is the "flight or fight" branch that controls swift responses to a threat. The parasympathetic branch (P) is "the rest and digest" branch which operates when we are at ease and feel safe. Therefore I think the answer in the text (Appendix H, page A-25) is wrong.
